Follow up question to Volvo post

[wrvdb]

Original post is:

http://forums.iboats.com/showthread.php?t=344052&highlight=volvo

What are the possible ways to get gas into your oil? I will be pulling my engine next week to replace the cam. The mechanic told me that the reason the lobes wore was because of thin oil (gas in it). He said it is either from the fuel pump or the holly carb. How do I trouble shoot this? Thanks

Volvo 3.0 gs

Thanks

 

[Robj]

Re: Follow up question to Volvo post

Gas in oil is commonly casued by a leaking fuel pump diaphram. There should be a clear line running from your fuel pump to the top of the carb. If this line has fuel in it, then the diaphram is leaking and the fuel pump needs to be changed. If there is no clear line running from the fuel pump, then you have an automotive pump and it needs to be changed to a marine pump.

Have a great day

Rob.

 

[Maclin]

Re: Follow up question to Volvo post

If the carb is leaking enough fuel from its' fuel bowl directly into the intake to get past the rings and thin the oil then you WILL have severe drivability problems due to a flooding condition. It will be hard to start, will not have any power until higher rpms and will backfire and just have generally horrible throttle response. While the engine is off the bowl will drain, and residual fuel pressure will allow even more fuel into the bowl until the pressure dissipates.

Holleys have a power valve with a rubber diaphragm, if it ruptures then the fuel will drain from the bowl directly into the throttle bores and on into the intake. But like I said, if this has happened you will definitely have the symptoms described earlier.

The only other way to get fuel into the oil is from an internally failing fuel pump diaphragm(s).

 

[wrvdb]

Re: Follow up question to Volvo post

Thanks for the response. Given what you guys said it has to be the fuel pump.